The first leg between Real Madrid and Manchester United is arguably the most attractive tie of the Round of 16 in the Champions League this season. Cristiano Ronaldo will be squaring off against his former team for the first time while Sir Alex Ferguson and Jose Mourinho will go head-to-head once more. With the various sub-plots, the attacking nature of both sides and the way their respective seasons have panned out so far, this encounter has all the makings of a real European classic.

FORMATIONS AND TACTICS

How Real Madrid Attack4-2-3-1

How Manchester United Defend4-3-3

Karim Benzema's hold-up play and pace on the counter-attack normally earns him the lone-striker role in big games and he should be the one starting against United. He will be flanked on either side by the threatening Angel Di Maria and the phenomenal Ronaldo. A lot of their play does come down the left hand side with Ronaldo looking to get at the right-back as much as possible but he will also drift inside to lose his marker. Mesut Ozil will be entrusted with orchestrating play in the final third. Sami Khedira often ventures forward to arrive late in the box to attack crosses.

Meanwhile, Xabi Alonso will be the premier distributor from his vantage point around the center circle. He will look to spray long-diagonal balls out wide to Ronaldo and Di Maria or either of their full-backs who push forward to support the attack. The two wingers, especially Ronaldo, have a knack for making diagonal runs in between the full-back and center-back. Alonso and Ozil will be keeping an eye out for those runs in particular. Even Sergio Ramos can get involved when he strides past the half-line and looks to pick out a ball over the top of the defense like he did for the opening goal against Sevilla on Saturday, although it's unlikely that United would employ a high-line which is so common in La Liga.

The visiting United side is bound to have a workman-like look to it. The main focus will be on containing Ronaldo and that's why the deployment of Phil Jones could be the key. He is a slight doubt for the game but should recover in time. He kept Marouane Fellaini on a short leash on Sunday, demonstrating his discipline and intelligence but his role this time around could be similar to the one he played when United drew 1-1 away to Tottenham last month. Jones shifted more to the right when defending to help Rafael deal with Gareth Bale and the duo could double-team Ronaldo at the Bernabeu.

Danny Welbeck will also track back and help out while keeping an eye on Fabio Coentrao who likes to get forward himself. Rio Ferdinand was rested on Sunday while Nemanja Vidic dominated defensively against Everton. The experienced center-backs could line-up together again for this high-profile fixture. Shinji Kagawa has plenty of energy as well and should start the game although he may not complete it. He will switch positions with Wayne Rooney on occasion who will be playing in an attacking midfield role and will slot in to cover central midfield alongside Carrick when Jones goes out to the right to deal with Ronaldo.

Note: Xabi Alonso is a slight doubt at the moment so Luka Modric will probably take his place (as depicted in the formation tables) if he doesn't recover in time.

How Real Madrid Defend4-2-3-1

How Manchester United Attack4-3-3

Madrid do commit a lot of bodies forward but they also get back very quickly. Ronaldo won't track back as much, instead he positions himself for the counter. Khedira and Alonso both fall back while the latter often has to shuttle out towards the left hand side to cover for Ronaldo. Fabio Coentrao has been preferred over Marcelo, who isn't at his best since coming back from an injury.

The two deep-lying midfielders is the insurance Mourinho likes to have. Khedira will be the more defensive of the two and will cover a lot more ground than his central midfield partner as well. It's his job to break up opposition attacks and distribute the ball to the more creative players. The center-backs will have to deal with the threat of Van Persie who is so clever with his movement while Rooney will also cause problems, not to mention Welbeck's diagonal runs in behind the defense.

Welbeck could feature in place of Antonio Valencia for this game primarily because United will have to be very intelligent with their movement in attack, especially on the break. What the foursome of Welbeck, Van Persie, Rooney and Kagawa offers is the ability to interchange at will while the link-up play within that group is exceptional at times. Each of those players are intelligent with their movement and can facilitate intricate play to get in behind what usually is a high-line set by Madrid's defenders.

Both full-backs will come forward to support the attack but they won't be too anxious to do so because Madrid pose a very serious threat on the counter-attack. Jones will stride forward occasionally but he and Rafael won't do so at the same time. Rooney and Kagawa will especially interchange positions on a regular basis. Carrick will be the one on the look out for Van Persie's movement up front and will attempt to pick him out with a long ball over the Madrid defense. On the counter-attack, Van Persie will be the one to hold up the ball and release a runner. Welbeck will be the most likely outlet with his pace down the right hand side while Rooney should be quick to get up the pitch in support of Van Persie as well.

ANALYSIS

Strengths –

Real Madrid: The La Liga champions have quality all over the pitch and on their day they can beat the anyone. Ronaldo is quite clearly their most lethal weapon but they have the players around him to give him the support he needs. Ozil is getting back into some good form after a difficult start to the season and when the German is on song, it makes a real difference to their play in the final third. With Di Maria and Benzema also in attack, they have plenty of pace which is well utilized especially on the counter-attack. Madrid are arguably the best counter-attacking side in club football at the moment and Alonso has a lot to do with that as he is usually the instigator of those breaks with his long passes.

Manchester United: The Red Devils have made it emphatically clear that their strengths lie in attack. They don't need to create too many chances to score and it's that clinical nature that could prove to be vital at the Bernabeu. Van Persie is a big-game player and isn't fazed by the pressure of the occasion while Rooney will be up for the task as well. The availability of their best central defensive pairing of Vidic and Ferdinand will be a massive boost for them while David de Gea is getting better and should be more comfortable playing in Europe. The same could be said of Kagawa who has found the physicality of the Premier League challenging but could put in one of his better performance against the Spanish outfit. United could also have an advantage from set-pieces. Van Persie's delivery is exceptional while the likes of Vidic, Jones, Ferdinand and also Evra posing serious threats from those situations.

Weaknesses –

Real Madrid: The fact that United have been prolific from set-pieces will worry Mourinho because his side have leaked a few goals from dead-ball situations this season. The defense has conceded too many goals in general as well with Ramos often being held responsible. Their keeper situation is also a cause for concern. Lopez is more experienced and seems more reliable than Adan but there's no doubt that they will miss the presence and at times crucial saves that Iker Casillas is so accustomed to making. With Ronaldo not tracking back, their left hand side could be exposed especially if Coentrao also gets caught up the pitch.

Manchester United: De Gea is in better shape than he was at the start of the season but he still looks nervy when a ball is launched into his area. Rafael has been a much improved player this season but Evra remains a liability at times. The Frenchman could be exposed with Di Maria cutting in on his left and which could leave the left-back wrong-footed. Their experienced center-backs is a boost but the fact remains that they are terribly short of pace and if Benzema, Di Maria or Ronaldo get a run at them, there's no way they will be able to keep up.

Madrid Key Player: Cristiano Ronaldo

United Key Player: Robin van Persie

All eyes will be on Cristiano Ronaldo as he lines up against his former team-mates and in all honesty, he wouldn't have it any other way. The former United number 7 hasn't missed a step since joining Los Blancos, improving on his goal-scoring and becoming equally important to his current side as he was to his last. He is undoubtedly their premier attacking threat and his hat-trick over the weekend bodes well for the hosts.

He still possesses that electric pace that saw so many Premier League defenders lie helplessly in his wake. If allowed any sort of space around the box, he is deadly from range with either foot. With his quite incredible ability to hang in the air longer than others, he's a constant threat from set-pieces. Most of all, his quick feet can dazzle the best defenders on his day and he's always capable of that bit of magic when his side need it the most.

Robin van Persie is arguably the first player to restore a certain level of star-quality to United's first team since Ronaldo's departure. As the lone striker, the Dutchman won't be the most involved player on the pitch but it's what he's capable of when he does come into play that makes him the key man. His clinical finishing may be the difference between the two sides.

Van Persie is well short of the kind of pace to trouble Ramos and Varane who are two of the quicker center-backs around but he does have the intelligence and experience to get the better of them. Ramos can get a little too tight on his man at times and Van Persie is an expert in drawing defenders in before spinning away to get in behind. He is accomplished at holding the ball up and bring others into play which will be crucial at the Bernabeu. He has the ability to create space for himself and if he gets a chance to let fly with his left foot, Diego Lopez will have a tough time handling him.

Who do you think will win this tie? Leave your comments below or discuss with the writer on Twitter @BrendonNetto.

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